Solvating system and sealant for medical use in the middle or inner ear

ABSTRACT

Chronic Otitis Media with Effusion (COME), Recurrent Acute Otitis Media (RAOM), cholesteatoma, and other bacterial ear conditions may be treated by applying a solvating system containing greater than 0.2 wt. % surfactant to a bacterial biofilm in the middle or inner ear, disrupting the biofilm, and applying a protective layer of a polymeric film-forming medical sealant.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of copending U.S. patentapplication Ser. No. 11/431,495 filed May 10, 2006, the entiredisclosure of which is incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to the treatment of chronic otitis media witheffusion (COME), Recurrent Acute Otitis Media (RAOM), cholesteatoma, andother bacterial ear conditions.

BACKGROUND

COME and RAOM are inflammatory diseases of the middle ear. Biofilmformation may be a factor in the pathogenesis of COME, see Post, J.C.,“Direct evidence of bacterial biofilms in otitis media”, Laryngoscope111(12):2083-94 (2001), Ehrlich et al., “Mucosal Biofilm Formation onMiddle-Ear Mucosa in the Chinchilla Model of Otitis Media”, JAMA287(13): 1710-15 (2002) and Fergie, N et al., “Is otitis media witheffusion a biofilm infection?”, Clin Otolaryngol Allied Sci. 29(1):38-46(2004). Biofilms form when bacteria interact with a surface to formpolymeric films (sometimes referred to as exopolysaccharide orextracellular polysaccharide polymers) that coat the surface and providea living colony for further bacterial proliferation. Bacteria lodged inbiofilms are much more difficult to remove or kill than bacteria in aplaktonic (suspended) state, and are extremely resistant to manyantibiotics and biocides. Both the extracellular polysaccharide (EPS)matrix and the toxins produced by a number of different bacteria havebeen shown to cause inflammation by the host. It appears that thechronic inflammation associated with COME and RAOM is a host response tothe bacterial biofilm.

COME and RAOM are usually initially treated using oral antibiotics andthen, if need be, are more aggressively treated by placement of atympanostomy tube. Occasionally in cases involving severe infection orhigh mucous content in the middle ear, the middle ear may be irrigated(e.g., with saline solution). While tympanostomy tubes work on mostpatients, about 20% of patients who undergo primary tympanostomy tubeplacement require an additional surgery (an adenoidectomy, a second setof tympanostomy tubes, and usually both an adenoidectomy andtympanostomy tube placement) to treat persistent COME or persistentRAOM.

Cholesteatoma is another ear disease condition of concern. Althoughgenerally thought to be primarily a cyst comprised of dermal cells,bacteria biofilms have also been implicated in this disease, see Choleet al., “Evidence for Biofilm Formation in Cholesteatomas”, ArchOtolaryngol Head Neck Surg. 128, pp. 1129-33 (October 2002). Incholesteatoma, bacterial biofilms appear to form, incite inflammation,and cause generation of a benign tumor composed mainly of bacteria atits core and dermal cells. The tumor can erode both the ossicular chain(hearing bones) and the mastoid bone, detrimentally affecting hearing.Surgical exposure and excision is the most common treatment forcholesteatoma removal. Up to 25% of these procedures fail due torecurrence of the cholesteatoma and thus require additional surgery orother treatment.

The etiology and chronicity of COME, RAOM and cholesteatoma appear to berelated to the presence of bacterial biofilms as well as theirrecalcitrance post-surgery.

SUMMARY OF THE INVENTION

Patients, and their parents in the case of children, dislike infectionrecurrence and the possible need to undergo repeat or additionalsurgery. Although antibiotics may initially be administered at elevateddosages to address these problems, antibiotics have been shown to beineffective against chronic infections that involve a bacterial biofilmand administering them can also promote drug resistance in the targetedand other bacterial species. It would be highly desirable to employalternative treatments that permit a reduction or elimination in theamount of required antibiotics yet discourage recurrence of the treatedcondition. When the treated condition involves a bacterial biofilm on atissue surface, it would be desirable to remove or disrupt the biofilmmore effectively than is the case when saline irrigation is employed, sothat remaining bacteria may more effectively be attacked by antibioticsor by the body's own natural defenses. It would also be desirable to atleast temporarily seal or otherwise protect the thus-treated surface inorder to repel bacterial adherence and biofilm reformation. It wouldalso be desirable to do so while meeting biocompatibility requirementsfor contact with human tissue, and while using small dosages ofadministered materials and short periods of application. Our copendingapplication Ser. No. (attorney docket no. 151-P-28476US01), filed evendate herewith, the entire disclosure of which is incorporated herein byreference, describes a solvating system comprising a metal ionsequestering agent and surfactant and its use to disrupt bacterialbiofilms within the middle or inner ear.

The present invention provides in one aspect a method for treatingchronic otitis media and other bacterial ear conditions, which methodcomprises:

-   -   a) applying a solvating system comprising greater than 0.2 wt. %        surfactant to a treatment site comprising a bacterial biofilm        attached or adhered to at least a portion of the middle or inner        ear,    -   b) detaching, removing or otherwise disrupting at least a part        of the biofilm, and    -   c) applying to the treatment site a protective layer of a        polymeric film-forming medical sealant.

The disclosed method may be used for treatment or post-operative care ofthe middle or inner ear, and may be used to treat maladies or chronicconditions including chronic otitis media with effusion, recurrent acuteotitis media, cholesteatoma and other bacterial ear conditions.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic cross-sectional view of a middle ear undergoingtreatment via the disclosed method.

FIG. 2 is an enlarged view of a portion of FIG. 1.

Like reference symbols in the various figures of the drawing indicatelike elements. The elements in the drawing are not to scale.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following detailed description describes certain embodiments and isnot to be taken in a limiting sense. All weights, amounts and ratiosherein are by weight, unless otherwise specifically noted. The termsshown below have the following meanings:

The term “antimicrobial agent” refers to a substance having the abilityto cause greater than a 90% numeric reduction (viz., at least a 1-logorder reduction) in a population of one or more of Staphylococcusaureus, Pseudomonas aeruginosa, Streptococcus pneumonia, Haemophilusinfluenzae or Moraxella catarrhalis or any other bacteria implicated inthe etiology of COME, RAOM or cholesteatoma using the bacterial platecount procedure described below in the Examples.

The terms “attached” and “adhered” when used in reference to a bacterialbiofilm and a surface mean that the biofilm is established on and atleast partially coats or covers the surface, and has some resistance toremoval from the surface. As the nature of this relationship is complexand poorly understood, no particular mechanism of attachment oradherence is intended by such usage.

The term “adhesion” refers to the sticking together of a material totissues or tissue to tissue with which it is in intimate contact forextended periods or tissue that connects opposing tissues or prostheticmaterials across a normally open space.

The term “bacterial biofilm” means a community of bacteria attached to asurface, with the organisms in the community being contained within anEPS matrix produced by the bacteria.

The term “biocompatible” when used in reference to a substance meansthat the substance presents no significant deleterious or untowardeffects upon the body.

The term “biodegradable” when used in reference to a substance meansthat the substance will degrade or erode in vivo to form smallerchemical species. Such degradation process may be enzymatic, chemical orphysical.

The term “bioresorbable” when used in reference to a substance meansthat the substance is capable of being absorbed by the body.

The terms “detaching”, “removing” and “disrupting” when used inreference to a bacterial biofilm attached or adhered to a surface meanthat at least a significant amount of the biofilm initially present onthe surface no longer is attached or adhered to the surface. Noparticular mechanism of detachment, removal or disruption is intended bysuch usage.

The term “hemostat” means a device or material which stops blood flow.

The term “polymeric sealant” means that the sealant is either formedfrom a synthetic crosslinked or uncrosslinked polymer or is a naturalmaterial such as a protein which has been crosslinked (e.g.,synthetically crosslinked).

The term “residence time” when used in reference to a polymeric sealantat a treatment site means the time period during which the sealantremains in place in vivo under gross observation.

The term “sequestering agent” means a chemical that will combine withanother material, especially a metal ion, to discourage or prevent thematerial from coming out of solution. The term “metal ion sequesteringagent” means a sequestering agent that will combine with one or moremetal ions such as alkali metals, alkaline earth metals, iron and thelike to discourage or prevent the metal ion from coming out of solution.In order of increasing atomic number the alkali metals are lithium,sodium, potassium, rubidium, cesium, and francium, and the alkalineearth metals are beryllium, magnesium, calcium, strontium, barium, andradium.

The term “solvating” means to form a solution or dispersion containing asolvent or other carrier within which a solute is dissolved orsuspended.

Referring to FIG. 1, the disclosed method may be performed within ear 10by inserting cannula 12 through ear canal 14 and ear tube 16 (which mayfor example have been installed via myringotomy) or other availableopening in tympanic membrane 18 and thence into middle ear 20. Cannula12 may also be inserted in other ways without myringotomy, such asthrough a needle or other guidance device directed through the ear,Eustachian tubes or nose, and operated blindly or by using guidedtechniques such as microendoscopy, virtual image guided endoscopy, orimage guided surgery using a flexible, tip tracked device. As shown inFIG. 1, the distal end 22 of cannula 12 is positioned above isthmus 24of Eustachian tube 26. Cannula 12 may be positioned and if need bemodified in shape or size so as to treat other portions of middle ear 20(which for purposes of this discussion will be deemed to include atleast the tympanic membrane, the lining of the middle ear, interiorstructures such as the ossicular chain and bordering structures such asthe mastoid) or to treat portions of the inner ear (which for purposesof this discussion will be deemed to include at least semicircularcanals 28 and cochlea 30). For example, if treatment in the inner ear isdesired, a further access opening (e.g., in a membrane near the roundwindow or oval window) may be made.

The solvating system may be directed through cannula 12 and applied tothe desired treatment site to detach, remove or otherwise disrupt atleast a part of a bacterial biofilm attached or adhered to at least aportion of the middle or inner ear. The solvating system desirably isapplied in at least an amount and thickness sufficient to cover thedesired portion of the biofilm. The treatment may involve chemicaldilution or mechanical disruption. For example, the solvating system maywith appropriate care be applied as a pressurized spray to dislodge thebacterial biofilm, bacteria and other foreign body buildup at thetreatment site. While not wishing to be bound by theory, the solvatingsystem may dissolve the biofilm and bring it into solution or suspensionso that the thus-disrupted biofilm can be easily flushed or otherwiseremoved from the treatment site using aspiration, lavage or otherremoval techniques performed via the myringotomy or through theEustachian tube or nose. Any remaining bacteria at the treatment sitemay then more readily be attacked by an antimicrobial agent or by thebody's natural defenses. Bacterial attack may for example be assisted byincluding an antimicrobial agent in the solvating system or in thepolymeric film-forming medical sealant, or by separately applying anantimicrobial agent intra operatively or post operatively (e.g.,topically, orally or systemically). It may be desirable to injectsufficient solvating system into the treatment area to displace any pusor other material that may be present, allowing excess material tooverflow from the treatment area until the color of the excess materialno longer changes. The solvating system may be left in place until itcan drain away or is otherwise eliminated or resorbed, or the solvatingsystem may be allowed to stand for a suitable time (e.g., a few minutes,a few hours or longer) and then may be rinsed away using saline oranother suitable liquid. The solvating system preferably is applieddirectly into the middle or inner ear region rather than merely beingapplied to the ear canal and allowed to transport across the tympanicmembrane, as such direct application may promote faster biofilm breakup.Application of the solvating system and removal of dislodged ordisrupted biofilm and bacteria may also be repeated as desired to ensurethorough removal of the offending organisms.

FIG. 2 shows an enlarged view of a portion of FIG. 1. The solvatingsystem is shown being applied to a bacterial biofilm proximate theEustachian tube isthmus by dispensing the solvating system throughorifices 34 located in sidewall 36 onto a bacterial biofilm such asbiofilm 38 disposed on upper portion 40 of Eustachian tube 26. Thoseskilled in the art will appreciate that the solvating system may beapplied to a desired treatment site using methods or devices other thancannula 12. Exemplary such methods include trephination and exemplarysuch devices include syringes (e.g., glass syringes and bulb syringes)and other devices suitable for providing access to the middle or innerear via the tympanic membrane, Eustachian tubes or nose.

To discourage bacterial recolonization and biofilm reformation, thepolymeric film-forming medical sealant is also applied to the treatmentsite. This may for example be accomplished using cannula 12 as shown inFIG. 1 and FIG. 2 to dispense the film-forming medical sealant onto thetreatment site. Those skilled in the art will appreciate that thesealant may be applied to the treatment site using methods or devicesother than cannula 12. The applied sealant may fill the middle or innerear when applied but desirably does not do so and instead preferably isapplied as a film or other conformal coating. The sealant desirablyadheres to natural tissues at the treatment site and resists detachmentor other disruption until natural degradation or resorption of thesealant takes place (e.g., after a residence time of one or more days orweeks). By applying only a coating rather than filling the treatmentsite, the ossicular chain may remain free to move with movement of thetympanic membrane due to sound pressure waves and the function of themiddle and inner ear may be preserved during healing. Meanwhilerecolonization or reinfection may be significantly reduced or prevented,and improved healing and reciliation may take place. If desired, thesealant may be applied to part or all of the ossicular chain or to partor all of the tympanic membrane in order to provide a degree ofstabilization during healing. The sealant may provide varioustherapeutic advantages including but not limited to bacterial adhesionrepellence, anti-infective properties, local immune modulation, tissueprotection, reduction or elimination of pain or bleeding, reduction ininflammation, optimization of environment for ciliary regrowth,reduction in adhesions to critical anatomy, or the like. Theseadvantages may arise due to a variety of mechanisms including a)inhibiting bacterial colonization, b) inhibiting the adherence ofbacteria to tissue, c) reducing tissue morbidity or abscess formation,d) reducing or preventing disease recurrence (for example, specificallyreducing the chronic inflammation related to bacterial toxin and EPS),e) coating and protecting tissue during healing, such as by maintenanceof a moist wound which promotes platelet aggregation, or by closure of adry wound without excessive scabrous formation, f) hemostasis, g)optimizing the environment for reciliation of the mucosa, h) speedingthe growth or regrowth of cilia, i) preventing adhesion of a prosthesisor tympanomucosal grafts to native tissue, and j) delivering therapeuticagent(s) to the treatment site. Desirably the sealant will attach to aportion of the mucosa, cover other portions of the mucosa while leavingthe cilia in such unattached portions free to undergo natural rhythmiccilia motion (viz., cilia beating), deliver antimicrobial agents oradditional therapeutic agents as needed, and prevent bacteria fromadhering to the treatment site.

A variety of solvating systems may be used in the disclosed method. Asnoted above, the solvating system comprises greater than 0.2 wt. %surfactant. The surfactant desirably is water-soluble and nontoxic.Exemplary surfactants include anionic surfactants, nonionic surfactants,cationic surfactants and zwitterionic surfactants. Exemplary anionicsurfactants include but are not limited to C₆-C₂₄ alkylbenzenesulfonates; C₆-C₂₄ olefin sulfonates; C₆-C₂₄ paraffin sulfonates; cumenesulfonate; xylene sulfonate; C₆-C₂₄ alkyl naphthalene sulfonates; C₆-C₂₄alkyl or dialkyl diphenyl ether sulfonates or disulfonates, C₄-C₂₄ monoor dialkyl sulfosuccinates; sulfonated or sulfated fatty acids; C₆-C₂₄alcohol sulfates (for example C₆-C₁₂ alcohol sulfates); C₆-C₂₄ alcoholether sulfates having 1 to about 20 ethylene oxide groups; C₄-C₂₄ alkyl,aryl or alkaryl phosphate esters or their alkoxylated analogues having 1to about 40 ethylene, propylene or butylene oxide units; and mixturesthereof. For example, the anionic surfactant may be sodiumchenodeoxycholate, N-lauroylsarcosine sodium salt, lithium dodecylsulfate, 1-octanesulfonic acid sodium salt, sodium cholate hydrate,sodium deoxycholate, sodium dodecyl sulfate (also known as sodium laurylsulfate) or sodium glycodeoxycholate.

Exemplary cationic surfactants include but are not limited to quaternaryamine compounds having the formula:

where R, R′, R″ and R′″ are each a C₁-C₂₄ alkyl, aryl or aralkyl groupthat can optionally contain one or more P, O, S or N heteroatoms, and Xis F, Cl, Br, I or an alkyl sulfate. For example, the cationicsurfactant may be hexadecylpyridinium chloride monohydrate orhexadecyltrimethylammonium bromide.

Exemplary nonionic surfactants include but are not limited to C₆-C₂₄alcohol ethoxylates (for example C₆-C₁₄ alcohol ethoxylates) having 1 toabout 20 ethylene oxide groups (for example about 9 to about 20 ethyleneoxide groups); C₆-C₂₄ alkylphenol ethoxylates (for example C₈-C₁₀alkylphenol ethoxylates) having 1 to about 100 ethylene oxide groups(for example about 12 to about 20 ethylene oxide groups); C₆-C₂₄alkylpolyglycosides (for example C₆-C₂₀ alkylpolyglycosides) having 1 toabout 20 glycoside groups (for example about 9 to about 20 glycosidegroups); C₆-C₂₄ fatty acid ester ethoxylates, propoxylates orglycerides; C₄-C₂₄ mono or di alkanolamides; and mixtures thereof. Forexample, the nonionic surfactant may be polyoxyethyleneglycol dodecylether, N-decanoyl-N-methylglucamine, digitonin, n-dodecyl B-D-maltoside,octyl B-D-glucopyranoside, octylphenol ethoxylate, polyoxyethylene (8)isooctyl phenyl ether, polyoxyethylene sorbitan monolaurate orpolyoxyethylene (20) sorbitan monooleate.

Exemplary zwitterionic surfactants include but are not limited toaminoalkylsulfonate compounds having the formula:

where R, R′, R″ and R′″ are each a C₁-C₂₄ alkyl, aryl or aralkyl groupthat can optionally contain one or more P, O, S or N heteroatoms; amineoxide compounds having the formula:

where R, R′ and R″ are each a C₁-C₂₄ alkyl, aryl or aralkyl group thatcan optionally contain one or more P, O, S or N heteroatoms; and betainecompounds having the formula:

where R, R′ and R″ are each a C₁-C₂₄ alkyl, aryl or aralkyl group thatcan optionally contain one or more P, O, S or N heteroatoms, and n isabout 1 to about 10. For example, the zwitterionic surfactant may be3-[(3-cholamidopropyl) dimethylammonio]-2-hydroxy-1-propane sulfonate,3-[(3-cholamidopropyl) dimethylammonio]-1-propane sulfonate (sometimesreferred to as CHAPS), 3-(decyldimethylammonio) propanesulfonate innersalt (sometimes referred to as caprylyl sulfobetaine), orN-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate.

Preferred surfactants include alkyl sulfates, alkyl sulfonates, arylsulfonates and zwitterionic surfactants. The desired surfactants may beobtained as pure compounds or in some instances may be obtained by usingproducts such as liquid Castile soap. The surfactant may for example bepresent at a concentration of at least about 0.002 M, at least about0.005 M or at least about 0.01 M, e.g., about 0.002 to about 1 M, about0.005 to about 0.7 M or about 0.01 to about 0.5 M. Expressed on a weightbasis, the surfactant is greater than 0.2 wt. % of the solvating systemand may for example be about 0.3% to about 30%, about 0.5% to about 25%or about 1% to about 20% of the solvating system. Increased surfactantamounts may promote faster biofilm breakup.

The solvating system may optionally contain a metal ion sequesteringagent. The sequestering agent desirably is a mild acid whose acidity issufficient to sequester one or more metal ions in the exopolysaccharideor extracellular polysaccharide matrix, but which is not so acidic so asto harm the treated middle or inner ear tissue. Metal ions of particularinterest (due to their likely involvement in the targeted bacterialbiofilms) include sodium, calcium and iron. The metal ion sequesteringagent desirably is water-soluble, nontoxic and not prone to aggravatelong-term hearing loss. Representative acids include but are not limitedto carboxylic acids, diacids, or triacids such as formic acid, aceticacid, chloroacetic acid, dichloroacetic acid, oxalic acid, oxamic acid,glycolic acid, lactic acid, pyruvic acid, aspartic acid, fumaric acid,maleic acid, succinic acid, iminodiacetic acid, glutaric acid,2-ketoglutaric acid, glutamic acid, adipic acid, citric acid, glucuronicacid, mucic acid, nitrilotriacetic acid, salicylic acid, ketopimelicacid, benzoic acid, mandelic acid, chloromandelic acid, phenylaceticacid, phthalic acid and boric acid; mineral acids such as hydrochloricacid, orthophosphoric acid and phosphonic acid; and mixtures thereof.Citric acid is a preferred acid. The metal ion sequestering agent mayfor example be present at a concentration of at least about 0.01 M, atleast about 0.05 M or at least about 0.1 M, e.g., about 0.01 to about0.5 M, about 0.05 to about 0.4 M or about 0.1 to about 0.3 M. Increasedmetal ion sequestering agent amounts may promote faster biofilm breakup.

The solvating system may optionally include a variety of otheringredients, including water and other solvents (e.g., alcohols),buffering agents, antimicrobial agents and a variety of adjuvants.Preferably the solvating system contains water and one or more bufferingagents. The buffering agent preferably maintains the solvating system atan appropriate pH for contacting human tissue, and desirably at a pHgreater than 5. For example, the solvating system may be buffered tohave a near-neutral pH, e.g., a pH greater than 5 and less than 8.5.Buffering agents may for example be up to about 25% of the solvatingsystem. Exemplary buffering agents include but are not limited topotassium chloride, glycine, potassium hydrogen phthalate, sodiumacetate, potassium hydrogen phthalate, barbitone sodium and sodiumcitrate. When the metal ion sequestering agent is a mild acid, thebuffering agent desirably is a salt of that acid.

Solvating systems containing one or more antimicrobial agents are alsopreferred. The EPS matrix allows the biofilm to stick to an underlyingsurface and also protects the embedded organisms; thus, bacteria inbiofilms are approximately 100 to 1000 times more resistant to theeffects of antibiotics than planktonic bacteria. After the biofilm hasbeen broken down into unbound polymers or fragments and solvated orotherwise disrupted by the solvating system, an antimicrobial agent canmuch more effectively attack the remaining bacteria. Exemplaryantimicrobial agents include active oxygen compounds such as hydrogenperoxide, isolated or equilibrium derived or isolated peracids such aschloroperbenzoic acids, peracetic acid, perheptanoic acid, peroctanoicacid, perdecanoic acid, performic acid, percitric acid, perglycolicacid, perlactic acid, perbenzoic acid, and monoester peracids derivedfrom diacids or diesters such as adipic, succinic, glutaric, or malonicacid; amphenicols; ampicillins; ansamycins; beta-lactams such ascarbacephems, carbapenems, cephalosporins, cephamycins, monobactams,oxacephems, penicillins and any of their derivatives; carboxylic esterssuch as p-hydroxy alkyl benzoates and alkyl cinnamates; chitosan salts;cubic-phase lipids; gallium-containing antimicrobial agents such asgallium acetylacetonate, gallium bromide, gallium chloride, galliumfluoride, gallium iodide, gallium maltolate, gallium nitrate, galliumnitride, gallium percolate, gallium phosphide and gallium sulfate;iodo-compounds and other active halogen compounds such as iodine,interhalides, polyhalides, metal hypochlorites, hypochlorous acid, metalhypobromites, hypobromous acid, chloro- and bromo-hydantoins, chlorinedioxide and sodium chlorite; lincosamides; macrolides; nitrofurans;organic peroxides including benzoyl peroxide and alkyl benzoylperoxides; ozone; phenolic derivatives including o-phenyl phenol,o-benzyl-p-chlorophenol, tert-amyl phenol and C₁-C₆ alkyl hydroxybenzoates; quaternary ammonium compounds such as alkyldimethylbenzylammonium chloride and dialkyldimethyl ammonium chloride; quinolines;singlet oxygen generators; sulfonamides; sulfones; sulfonic acids suchas dodecylbenzene sulfonic acid; tetracyclines; vancomycin; derivativesthereof and mixtures thereof. Many of these recited agents representclasses containing useful specific materials whose individual utilitywill be recognized by persons having ordinary skill in the art. Forexample, exemplary penicillins include but are not limited toamdinocillin, amdinocillin pivoxil, amoxicillin ampicillin, apalcillin,aspoxicillin, axidocillin, azlocillin, acampicillin, bacampicillin,benzylpenicillinic acid, benzylpenicillin sodium, carbenicillin,carindacillin, clometocillin, cloxacillin, cyclacillin, dicloxacillin,epicillin, fenbenicillin, floxacillin, hetacillin, lenampicillin,metampicillin, methicillin sodium, mezlocillin, nafcillin sodium,oxacillin, penamecillin, penethamate hydriodide, penicillin Gbenethamine, penicillin G benzathine, penicillin G benzhydrylamine,penicillin G calcium, penicillin G hydrabamine, penicillin G potassium,penicillin G. procaine, penicillin N, penicillin O, penicillin V,penicillin V banzathine, penicillin V hydrabamine, penimepicycline,phenethicillin potassium, piperacillin, pivampicillin propicillin,quinacillin, sulbenicillin, sultamicillin, talampicillin, temocillin,ticarcillin and mixtures thereof or with other materials (e.g.,penicillins combined with clavulanic aid such as the combination ofamoxicillin and clavulanic acid available as AUGMENTIN™ fromGlaxoSmithKline).

An antimicrobial agent such as those described above may optionally beapplied in a separate treatment step (if need be in a suitable carrier)after application of the solvating system and before application of thepolymeric film-forming medical sealant. An antimicrobial agent may alsobe applied as a part of the sealant. Whether applied as a part of thesolvating system, in a separate step, or as a part of the sealant, theantimicrobial agent preferably provides greater than a 99% numericreduction (viz., at least a 2-log order reduction), greater than a 99.9%numeric reduction (viz., at least a 3-log order reduction), greater thana 99.99% numeric reduction (viz., at least a 4-log order reduction) orgreater than a 99.999% numeric reduction (viz., at least a 5-log orderreduction) in a population of one or more of S. aureus, P. aeruginosa,S. pneumonia, H. influenzae or M. catarrhalis bacteria using thebacterial plate count procedure described below in the Examples.

The solvating system may contain additional therapeutic agents.Exemplary therapeutic agents include any material suitable for otologicuse including analgesics, anti-cholinergics, anti-fungal agents,antihistamines, steroidal or non-steroidal anti-inflammatory agents,anti-parasitic agents, antiviral agents, biostatic compositions,chemotherapeutic/antineoplastic agents, cytokines, decongestants,immunosuppressors, mucolytics, nucleic acids, peptides, proteins,steroids, vasoconstrictor's, vitamins, mixtures thereof, and othertherapeutic materials that will be apparent to those skilled in the art.Several such additional therapeutic agents are discussed in more detailbelow in connection with the polymeric film-forming medical sealant.Other adjuvants that may be included in the solvating system includedyes, pigments or other colorants (e.g., FD & C Red No. 3, FD & C RedNo. 20, FD & C Yellow No. 6, FD & C Blue No. 2, D & C Green No. 5, D & COrange No. 4, D & C Red No. 8, caramel, titanium dioxide, fruit orvegetable colorants such as beet powder or beta-carotene, turmeric,paprika and other materials that will be familiar to those skilled inthe art); indicators; flavoring or sweetening agents including but notlimited to anise oil, cherry, cinnamon oil, citrus oil (e.g., lemon,lime or orange oil), cocoa, eucalyptus, herbal aromatics (e.g., cloveoil, sage oil or cassia oil), lactose, maltose, menthol, peppermint oil,saccharine, sodium cyclamate, spearmint oil, sorbitol, sucrose,vanillin, wintergreen oil, xylitol and mixtures thereof; antioxidants;antifoam agents; and rheology modifiers including thickeners andthixotropes.

The solvating system desirably has a sufficiently low viscosity toenable easy delivery to the treatment site using for example power sprayor other spray application, lavage, misting, mopping, wicking ordripping. The solvating system desirably also may be easily removed fromthe treatment site by subsequent flushing, rinsing, draining orabsorption. The solvating system need not be applied in liquid form andmay for example be applied as a powder, gel, foam, sponge, film strip orother suitable form. The solvating system may be applied to treatmentsites in the middle or inner ear or in associated structures such as theEustachian tubes. The solvating system is biocompatible with thedelicate tissues and structures of the middle or inner ear, anddesirably does not contain ingredients which might potentially harm suchtissues or structures or unduly compromise long-term hearing.

A variety of polymeric film-forming medical sealants may be used in thedisclosed method. The sealant preferably is a biodegradable orbioresorbable material having a residence time in vivo of from one dayto a few (e.g., 2, 3 or 4) days, weeks or months. The sealant may beuncrosslinked, crosslinked before being applied to the treatment site,or crosslinked after application. In one embodiment, the sealant may bea viscoelastic material. In another embodiment, the sealant may hardenafter application. The sealant may be a synthetic polymer (for example,polyethylene glycol or PEG), natural polymer (for example, apolysaccharide, lipid or polypeptide), or a synthetically-modifiednatural polymer (for example, a polypeptide reacted with PEG). Otherexemplary synthetic polymers include polyacetals, polyacrylic acid,polyalkylene oxalates, polyalkylene succinates, polyamides, polyaminoacids, polyaspartic acid, polyanhydrides, polycaprolactones,polycarbonates, polycyanoacrylates, polydiaxonones, polyesteramides,polyetheresters, polyethylene oxide (PEO), poly(glycolic acids) andother poly(glycolides), polyhydroxybutyrates, polyhydroxyvalerates,polyketals, poly(lactic acid) and other polylactides includingpoly(lactide-co-glycolides), poly(malic acids), polyorthoesters,polyphosphazines, polyphosphoesters, polypropylene oxide (PPO),degradable polyurethanes, polyvinyl alcohol (PVA), polyvinyl pyrrolidone(PVP), and copolymers, terpolymers, blends, and mixtures thereof.

Exemplary polysaccharides include cellulose and its derivatives such asoxidized cellulose, hydroxyethyl cellulose, carboxymethyl cellulose(CMC), carboxymethyl amylose (CMA), carboxyethyl cellulose andhydroxypropylmethyl cellulose (HPMC); chitin; chitosan and itsderivatives such as carboxymethyl chitosan and trimethylchitosan;dextran and its derivatives such as carboxymethyl dextran; glycogen;glycosaminoglycans such as hyaluronan (e.g., hyaluronic acid and itsderivatives including esters and polymers), heparin, heparin sulfate,dermatin sulfate, and chondroitin-6-sulfate; gums such as alginate,gellan gum and xanthan gum; pectin; and starch and its derivatives.

Exemplary lipids include glyceryl based lipid compounds such as glycerylmonooleate, and liquid crystal lipids which can be delivered in fluidform and which when in contact with moisture will convert to a cubicphase to provide a waxy cubic or crystalline material.

Exemplary polypeptides include albumin, collagen, gelatin, silk andtheir derivatives. For example, crosslinked hydrogels may be formed frommany polypeptides by reacting them with a suitable crosslinking agentsuch as an aldehyde (e.g., glutaraldehyde or formaldehyde),carbodiimide, chitin, CMC or a glycol such as a PEG.

The polymeric film-forming medical sealant may include antimicrobialagents, additional therapeutic agents and other adjuvants like thosementioned above in connection with the solvating system. Sealantscontaining therapeutic agents that offer both anti-infective andanti-inflammatory properties (e.g., tetracyclines) are a preferredembodiment. Sealants containing additional therapeutic agents such asanti-fungal agents, antihistamines, steroidal or non-steroidalanti-inflammatory agents, anti-parasitic agents, antiviral agents,chemotherapeutic/antineoplastic agents, decongestants or mucolytics areanother preferred embodiment. Sealants containing antimicrobial agentsand additional therapeutic agents are yet another preferred embodiment.Exemplary anti-fungal agents include but are not limited to allylamines,imidazoles, polyenes, thiocarbamates, triazoles, derivatives thereof andmixtures thereof. Exemplary antihistamines include but are not limitedto azelastine, diphenhydramine, loratidine, derivatives thereof andmixtures thereof. Exemplary steroidal anti-inflammatory agents includebut are not limited to 21-acetoxypregnenolone, alclometasone, algestone,amcinonide, beclomethasone, betamethasone, budesonide, chloroprednisone,clobetasol, clobetansone, clocortolone, cloprednol, corticosterone,cortisone, cortivazol, deflazacort, desonide, desoximetasone,dexamethasone, diflorasone, diflucortolone, difluprednate, enoxolone,fluazacort, flucloronide, flumethasone flunisolide, fluocinoloneacetonide, fluocinonide, fluocortin butyl, fluocortolone,fluorometholone, fluperolone acetate, fluprednidene acetate,fluprednisolone, flurandrenolide, fluticasone propionate, formocortal,halcinonide, halobetasol propionate, halometasone, halopredone acetate,hydrocortamate, hydrocortisone, loteprednol etabonate, mazipredone,medrysone, meprednisone, methylprednisolone, mometasone furoate,paramethosone, prednicarbate, prednisolone, prednisolone25-diethylamino-acetate, prednisolone sodium phosphate, prednisone,prednival, prednylidene, rimexolone, tixocortol, triamcinolone,triamcinolone acetonide, triamcinolone benetonide, triamcinolonehexacetonide, derivatives thereof and mixtures thereof. Preferredsteroidal anti-inflammatory agents include beclomethasone, budesonide,fluticasone proprionate and mometasonefuroate. Exemplary nonsteroidalanti-inflammatory agents include but are not limited to COX inhibitors(COX-1 or COX nonspecific inhibitors) and selective COX-2 inhibitors.Exemplary COX inhibitors include but are not limited to salicylic acidderivatives such as aspirin, sodium salicylate, choline magnesiumtrisalicylate, salicylate, diflunisal, sulfasalazine and olsalazine;para-aminophenol derivatives such as acetaminophen; indole and indeneacetic acids such as indomethacin and sulindac; heteroaryl acetic acidssuch as tolmetin, dicofenac and ketorolac; arylpropionic acids such asibuprofen, naproxen, flurbiprofen, ketoprofen, fenoprofen and oxaprozin;anthranilic acids (fenamates) such as mefenamic acid and meloxicam;enolic acids such as the oxicams (piroxicam, meloxicam); alkanones suchas nabumetone; derivatives thereof and mixtures thereof. Exemplary COX-2inhibitors include but are not limited to diaryl-substituted furanonessuch as refecoxib; diaryl-substituted pyrazoles such as celecoxib;indole acetic acids such as etodolac and sulfonanilides such asnimesulide; derivatives thereof and mixtures thereof. Exemplaryanti-parasitic agents include but are not limited to atovaquoneclindamycin, dapsone, iodoquinol, metronidazle, pentamidine, primaquine,pyrimethamine, sulfadiazine, trimethoprim/sufamethoxazole, trimetrexate,derivatives thereof and mixtures thereof. Exemplary antiviral agentsinclude but are not limited to acyclovir, famciclovir, valacyclovir,edoxudine, ganciclovir, foscamet, cidovir (available as VISTIDE™ fromGilead Sciences, Inc.), vitrasert, formivirsen, HPMPA(9-(3-hydroxy-2-phosphonomethoxypropyl)adenine), PMEA(9-(2-phosphonomethoxyethyl)adenine), HPMPG(9-(3-hydroxy-2-(phosphonomethoxy)propyl)guanine), PMEG(9-[2-(phosphonomethoxy)ethyl]guanine), HPMPC(1-(2-phosphonomethoxy-3-hydroxypropyl)-cytosine), ribavirin, EICAR(5-ethynl-1-beta-D-ribofuranosylimidazole-4-carbonxamine), pyrazofurin(3-[beta-D-ribofuranosyl]-4-hydroxypyrazole-5-carboxamine),3-Deazaguanine, GR-92938X(1-beta-D-ribofuranosylpyrazole-3,4-dicarboxamide), LY253963(1,3,4-thiadiazol-2-yl-cyanamide), RD3-0028(1,4-dihydro-2,3-benzodithiin), CL387626 (4,4′-bis[4,6-di][3-aminophenyl-N,N-bis(2-carbamoylethyl)-sulfonilimino]-1,3,5-triazine-2-ylamino-biphenyl-2-,2′-disulfonicacid disodium salt), BABIM (bis[5-amidino-2-benzimidazoly-1]-methane),NIH351, derivatives thereof and mixtures thereof. Exemplarychemotherapeutic/antineoplastic agents include but are not limited toantitumor agents (e.g., cancer chemotherapeutic agents, biologicalresponse modifiers, vascularization inhibitors, hormone receptor blocks,and cryotherapeutic agents or other agents that destroy or inhibitneoplasia or tumorigenesis) such as alkylating agents or other agentswhich directly kill cancer cells by attacking their DNA (e.g.,cyclophosphamide and isophosphamide), nitrosoureas or other agents whichkill cancer cells by inhibiting changes necessary for cellular DNArepair (e.g., carmustine (BCNU) and lomustine (CCNU)), antimetabolitesand other agents that block cancer cell growth by interfering withcertain cell functions, usually DNA synthesis (e.g., 6 mercaptopurineand 5-fluorouracil (5FU)), antitumor antibiotics and other compoundsthat act by binding or intercalating DNA and preventing RNA synthesis(e.g., doxorubicin, daunorubicin, epirubicin, idarubicin, mitomycin-Cand bleomycin), plant (vinca) alkaloids and other anti-tumor agentsderived from plants (e.g., vincristine and vinblastine), steroidhormones, hormone inhibitors, hormone receptor antagonists and otheragents which affect the growth of hormone-responsive cancers (e.g.,tamoxifen, herceptin, aromatase inhibitors such as aminoglutethamide andformestane, triazole inhibitors such as letrozole and anastrazole, andsteroidal inhibitors such as exemastane), antiangiogenic proteins, smallmolecules, gene therapies or other agents that inhibit angiogenesis orvascularization of tumors (e.g., meth-1, meth-2 and thalidomide),bevacizumab (available as AVASTIN™ from Genentech), squalamine,endostatin, angiostatin, ANGIOZYME™ from Ribozyme Pharmaceuticals,neovastat (available as AE-941 ™ from Aetema Zentaris), CC-5013(available as REVIMID™ from Celgene Corp.), medi-522 (available asVITAXIN™ from MedImmune, Inc.), 2-methoxyestradiol or 2ME2 (available asPANZEM™ from Entremed, Inc.), carboxyamidotriazole (CAI), combretastatinA4 prodrug (CA4P), SU6668, SU11248, BMS-275291, COL-3, EMD 121974,IMC-1C11, IM862, TNP-470, celecoxib (available as CELEBREX™ from PfizerInc.), refecoxib, interferon alpha, interleukin-12 (IL-12) or any of thecompounds identified in Science Vol. 289, Pages 1197-1201 (Aug. 17,2000) which is expressly incorporated herein by reference, biologicalresponse modifiers (e.g., interferon, bacillus calmette-guerin (BCG),monoclonal antibodies, interluken 2, granulocyte colony stimulatingfactor (GCSF), etc.), PGDF receptor antagonists, herceptin,asparaginase, busulphan, carboplatin, cisplatin, carmustine,chlorambucil, cytarabine, dacarbazine, etoposide, flucarbazine,flurouracil, gemcitabine, hydroxyurea, ifosphamide, irinotecan,lomustine, melphalan, mercaptopurine, methotrexate, thioguanine,thiotepa, tomudex, topotecan, treosulfan, vinblastine, vincristine,mitoazitrone, oxaliplatin, procarbazine streptocin, taxol or paclitaxel,taxotere, analogs/congeners, derivatives thereof and mixtures thereof.Exemplary decongestants include but are not limited to epinephrine,oxymetazoline, phenylephrine, pseudoephedrine, tetrahydrozolidine,xylometazoline, derivatives thereof and mixtures thereof. Exemplarymucolytics include but are not limited to acetylcysteine, dornase alpha,guaifenesin, derivatives thereof and mixtures thereof.

In those instances where it is desirable to remove water from tissue,e.g., to remove fluid from edematous tissue, a hyperosmolar agent may beemployed in the sealant. Exemplary hyperosmolar agents include but arenot limited to furosemide, sodium chloride gel and other saltpreparations that draw water from tissue or substances that directly orindirectly change the osmolar content of the mucous layer. Wheresustained release or delayed release of the therapeutic agent isdesirable, a release agent modifier may also be included in the sealant.

The sealant desirably has a sufficiently low viscosity to enable easydelivery to the treatment site using for example power spray or otherspray application, lavage, misting, mopping, wicking or dripping. Thesealant need not be applied in liquid form and may for example beapplied as a powder, gel, foam, sponge, film strip or other suitableform. The sealant may be applied to treatment sites in the middle orinner ear or in associated structures such as the Eustachian tubes. Theapplied sealant may be bioresorbable or biodegradable after a desiredperiod of time once healing has occurred. The sealant desirably includesat least one characteristic that promotes retention of the sealant atthe treatment site. This characteristic may be selected from a varietyof features including but not limited to thickness, size, shape,density, viscosity, hardness, bioadhesiveness, mucoadhesiveness, mannerof application or insertion, and the like. The sealant may preventbacterial recolonization or the formation or reformation of bacterialbiofilms by covering the treatment site (e.g., mucosa from which abacterial biofilm has been removed by the solvating system) with analternative film structure whose surface is not readily penetrable bybacteria associated with bacterial ear conditions. The sealant isbiocompatible with the delicate tissues and structures of the middle orinner ear, and desirably does not contain ingredients which mightpotentially harm such tissues or structures or unduly compromiselong-term hearing.

The solvating system and sealant may desirably be used as a part of amulti-step treatment regimen which disrupts the bacterial biofilm anddiscourages its return. For example, a series of steps that may bebroadly classified as Cleansing/Disrupting, Killing, Protecting/Coating,Aerating, and Healing may be carried out. The Cleansing/Disrupting stepmay be carried out by administering the solvating system as describedabove. The Killing step may be carried out by applying a suitableantimicrobial agent to the treatment site. This may as described abovebe accomplished by including an antimicrobial agent in the solvatingsystem, in the sealant, or in both the solvating system and sealant. Asnoted above, an antimicrobial agent may also be applied as a separatestep between application of the solvating system and application of thesealant. An antimicrobial agent may also be applied or administered postoperatively. The Protecting/Coating step may be carried out by coatingat least part of the thus-treated tissue with a protective sealant layeras described above. The Aerating step may be carried out by preservingor forming a suitable opening or openings (e.g., a slit in the tympanicmembrane) and leaving it or them open for a period of time sufficient toallow aeration of the treated ear region. The time period may beaffected by the nature of the opening(s) and by whether or not atympanostomy tube is installed. For example, if a slit has been formedin the tympanic membrane and a tube is not placed in the opening thenthe slit may remain open for a few days and heal over, thereby closingthe ear space naturally. The Healing step may be carried out by allowingthe cleansed, protected and sealed tissue surface to undergo a return toa normal state, e.g., through one or more healing mechanisms such asmodulation of an inflammatory response, phagocytosis, mucosalremodeling, reciliation or full or partial restoration of normal hearingor balance.

A comparable series of steps may be performed in a multi-step treatmentregimen which disrupts a bacterial biofilm in a sinus cavity. Furtherdetails regarding such a regimen may be found in copending applicationSer. No. (attorney docket no. 151-P-28325US01), filed even dateherewith, the entire disclosure of which is incorporated herein byreference.

The invention is further illustrated in the following non-limitingexamples.

EXAMPLE 1

As a proxy for the S. aureus and P. aeruginosa bacteria that may beimplicated in bacterial biofilms in the middle ear (other bacteria thatmay be implicated include S. pneumonia, H. influenzae and M.catarrhalis), bacterial isolates were recovered from the sinuses ofpatients with sinus disorders. Patients with cystic fibrosis or anunderlying immunosuppressive disease (HIV infection, insulin-dependentdiabetes mellitus, or renal disease) and patients who had takenantibiotics or oral prednisone in the previous month were excluded. Allpatients had refractory sinusitis, that is, persistent symptomsresistant to medical therapy despite having undergone technicallysuccessful functional endoscopic sinus surgery (FESS) for refractorychronic rhinosinusitis (CRS) with or without nasal polyposis. Theoccurrence of CRS was diagnosed in accordance with the 2003 AmericanAcademy of Otolaryngology-Head and Neck Surgery (AAO-HNS) guidelines setout in Benninger et al., “Adult chronic rhinosinusitis: Definitions,diagnosis, epidemiology, and pathophysiology”, Otolaryngol Head NeckSurg 129(3 suppl):S1-S32 (2003). The selected patients had beenrefractory to medical therapy for more than 12 months before samplecollection, and the failure of FESS was judged not to be associated withtechnical factors such as obstructive synechiae, frontal sinusobstruction, or a retained uncinate process. Samples were collectedconsecutively until 10 specimens each of S. aureus and P. aeruginosawere obtained using direct endoscopic guidance and the proceduredescribed by Nadel et al., “Endoscopically guided cultures in chronicsinusitis”, Am J Rhinol 12:233-241 (1998). Briefly, a topical anestheticagent was administered, the nasal ala retracted, and an endoscope usedto visualize the middle meatus and sinus cavities. A thin, flexiblecalcium alginate swab (STARSWAB II™ Collection and Transport System,Starplex Scientific, Etobicoke, Ontario) was inserted and directed tothe site with the most purulence. If no purulence was observed, thesurface of the maxillary sinus was swabbed for 15 seconds. Care wastaken to avoid contact with the lateral nasal wall or nasal vestibule.Samples were plated and incubated using standard procedures. Bacteriawere identified using a VITEK 2™ system (Biomerieux, Durham, N.C.).Crystal violet staining to confirm the presence of biofilms wasperformed according to the method described by Stepanovic et al., “Amodified microtiter-plate test for quantification of staphylococcalbiofilm formation”, J Microbiol Methods 40:175-179 (2000). Forincubation and culture, previously frozen strains were inoculated ontrypticase soy agar (TSA) with 0.5% sheep blood. After 24 hours, one tofour colonies per strain were cultured on TSA. Cultures were incubatedat 37° C. for 24 hours to condition them to a trypticase soy broth(TSB)-TSA medium and ensure noncontamination. Colonies grown on TSAsolid medium were then amplified in 5 mL of TSB medium with 0.5% glucoseaccording to the method described by Gotz, “Staphylococcus andbiofilms”, Mol Microbiol 43:1367-1378 (2002) and incubated at 37° C. forat least 24 hours.

A drip-flow reactor (DFR) was used to determine the effectiveness ofvarious test solutions delivered to S aureus and P aeruginosa biofilmson hydroxyapatite (HA)-coated microscope slides for removing thesebacterial biofilms with and without hydrodynamic force. The slides inthe DFR are tipped at 10° from the horizontal, thereby modeling a lowshear environment. The DFR was housed in an incubator at 37° C. underaerobic conditions. Approximately 20 minutes before bacterialinoculation, sterile medium (10% TSB for S aureus; 1% TSB for Paeruginosa) was dripped on the slides in the DFR and allowed to collectover the slides to form a conditioning layer. The slides were theninoculated with 1 mL of a culture of either S aureus or P aeruginosa.The DFR was tilted so that the slides would be horizontal for 4 hours toallow bacterial attachment to the substrate. Subsequently, the DFR wasset so that the slides were once again at a 10° angle, with sterilemedium dripping on the slides at a rate of 10 mL per hour. After 3 days,biofilm-removal experiments were performed. Two methods were used totreat the biofilms formed by each bacterial species. The firstapplication method involved a static treatment in the DFR, with asolvating agent (referred to as CAZS) being dripped onto the biofilms.The CAZS solvating agent contained deionized water, 25 g/L(corresponding to 0.13 M) citric acid, 5.35 g/L (corresponding to 0.02M) caprylyl sulfobetaine zwitterionic surfactant(CH₃(CH₂)₉N⁺(CH₃)₂CH₂CH₂CH₂SO₃ ⁻, CAS 15163-36-7) and sufficient sodiumcitrate (about 240 g/L) to buffer the system to pH 5.4. The secondapplication method involved delivery of saline or delivery of CAZSoutside the DFR, using a pressurized jet lavage to apply a hydrodynamicshearing force to the biofilm. For all treatments, preliminary runs weredone to ensure that variations among slides were within acceptablelimits. In addition, multiple plates of both bacterial species wereproduced to determine the within-run and run-to-run variations. Acontrol slide was made for each DFR run. Three runs were evaluated foreach treatment of each type of bacteria.

For static treatment, flow to the DFR was halted, the DFR was placed ina horizontal position, and the cover was removed. A 25 mL portion ofCAZS was applied to one slide. Control slides were not treated withCAZS. After 10 minutes, the slides were rinsed with saline (25 mL). TheDFR was then disconnected from the inflow tube, and each slide wasremoved under a laminar flow hood and placed in a sterile 50-mL tube.After another saline rinse (2 mL), the surface of the slide was scrapedrepeatedly, and the scrapings and saline were collected in the tube. Thetube was vortexed for 10 seconds, sonicated for 2 minutes, and vortexedagain for 10 seconds to disperse the bacteria into suspension. Thesuspensions were then serially diluted and 100 μmL aliquots applied tothree plates containing TSA and incubated at 37° C. for 24 hours.Colony-forming units (CFUs) were counted manually, and the number ofCFUs per square centimeter was calculated. The resulting plate countswere log (10) transformed and expressed as the mean (±SD) value derivedfrom plate counts from two DFR runs of three slides each.

For hydrodynamic treatment, the slides were removed from the DFR andplaced in a glove box. The slides were placed in a holder and sprayedfor approximately 20 seconds with about 150 mL of either saline or CAZSusing a device that provided pressurized jet lavage. The spraying wasdone with both a side-to-side and an up-and-down sweeping motion so thatall areas were sprayed twice, once in each axis. The slides were thenplaced in sterile 50-mL tubes, rinsed, scraped, dispersed, incubated andevaluated as described above.

The mean (±SD) percent reduction from control values in the quantity ofS. aureus and P. aeruginosa bacteria (viz., the number of CFUs on eachplate) after each treatment was calculated and the results assessedusing two-sample t tests (MINITAB™ version 14, Minitab, State College,Pa.). A P value less than 0.05 was considered to represent a significantdifference from the control value. The results are shown below in Table1, expressed as the mean (±SD) number of colony-forming units percentimeter (log) derived from three plates assessed twice:

TABLE 1 Bacterial Plate Log Counts According to Type of TreatmentTreatment Staphylococcus aureus Pseudomonas aeruginosa None (Control)8.7 ± 0.4 9.2 ± 0.2 Static CAZS delivery 6.2 ± 0.3 6.3 ± 1.3Hydrodynamic saline 6.4 ± 0.2 6.9 ± 0.1 delivery Hydrodynamic CAZS 4.8 ±0.3 4.0 ± 0.5 delivery

The results in Table 1 show that significant bacterial biofilm removalwas obtained. Before treatment, ample biofilms formed in the DFRcultures of both S. aureus and P. aeruginosa, with CFU counts for theseControls ranging from 7.8 to 9.5 log/cm². Static administration of CAZSresulted in a 2.5 log reduction (5.11×10⁸ to 1.65×10⁶; P=0.001) in thenumber of S. aureus CFUs and a 2.9 log reduction (1.69×10⁹ to 1.91×10⁶;P=0.002) in the number of P. aeruginosa CFUs. Mechanical disruptionusing hydrodynamic saline delivery alone decreased the number of S.aureus CFUs by 2.3 log units (5.11×10⁸ to 2.38×10⁶; P=0.001) and thenumber of P. aeruginosa CFUs by 2.4 log units (1.69×10⁹ to 7.31×10⁶;P=0.001). However, mechanical disruption using hydrodynamic CAZSdecreased the S. aureus CFU count by 3.9 log units (5.11×10⁸ to6.37×10⁴; P=0.001) and the P aeruginosa CFU count by 5.2 log units(1.69×10⁹ to 1.04×10⁴; P=0.001).

Confocal scanning laser microscopy (CSLM) was performed on three slides(for each treatment and bacteria species) not subjected to plate countsto allow imaging of the biofilm architecture in control and treatedsamples. The slides were stained for CSLM using a BACLIGHT™ Live/Deadkit (Molecular Probes, Invitrogen, Carlsbad, Calif.) containing twonucleic acid stains (SYTO 9, which detects living cells by fluorescinggreen, and propidium iodide, which detects dead cells by fluorescingred). After staining, the slides were examined using CSLM at a 630×magnification using a LEICA™ SP2 acoustic-optical beam splitter with a2-photon MAI TAI™ attachment (Leica Microsystems, Bannockburn, Ill.) andfluorescence excitation and detection in both the green and red spectra.Each slide area was divided into 10 equally sized segments. Amicroscopic field was selected at random from each segment, and imageswere obtained at 1-μm intervals from the top of the biofilm to thesubstrate, thereby creating an image stack for each location. The CSLManalysis revealed that a thick biofilm carpeted the Control slides.Hydrodynamic treatment with saline and static treatment with CAZSdecreased the amount of biofilm coverage markedly and reduced theorganization of the remaining biofilm. Hydrodynamic treatment with CAZSproduced a greater reduction both in biofilm coverage and in the amountof order in the biofilm community. The results corresponded generally tothe plate count assessments with respect to the relative reductions inthe amount of biofilm achieved with each treatment.

Of the three treatments investigated, power irrigation using CAZS and apressurized jet lavage was the most effective in disrupting thebacterial biofilms. Power irrigation using saline had appreciablebiofilm-reducing effects. However, the presence of a surfactant andcitric acid in the irrigation solution significantly enhanced thereduction in CFU count in both S. aureus and P. aeruginosa biofilms.Large, statistically significant reductions occurred, with the meandecreases in bacterial plate counts being 3.9 and 5.2 log (a reductionof 10,000 to 100,000 times), respectively, for S. aureus and P.aeruginosa biofilms. A decrease of this magnitude in vitro indicatesthat an appropriate in vivo treatment in the middle or inner ear shouldeffectively disrupt bacterial biofilms found there. Any remaining lowlevel of persistent bacterial infection might be dealt with by hostdefenses or a topically or orally administered antimicrobial agent, andby application of a sealant as described above.

EXAMPLE 2

Experimental work conducted using S aureus and P aeruginosa culturesgrown on TSA solid medium (viz., cultures made without use of HA-coatedglass slides and the DFR and less likely to include a durable biofilm)indicates that a solvating system containing the surfactant but no metalion sequestering agent may be less effective as a biofilm disrupter thana solvating system which also contains the metal ion sequestering agent.However, either solvating system may be a more effective biofilmdisrupter than saline solution.

EXAMPLE 3

The CAZS solvating system employed in Example 1 was modified byreplacing some of the water with gallium nitrate so that the modifiedsystem contained 25% gallium nitrate. A Control solution containing 25%gallium nitrate in deionized water was also prepared. When evaluatedusing the static treatment technique of Example 1, administration of thegallium nitrate Control solution resulted in a 3.4 log reduction(average of 4 runs) in the number of S. aureus CFUs and a 4.1 logreduction (average of 3 runs) in the number of P. aeruginosa CFUs.Static administration of the solution containing CAZS and galliumnitrate resulted in a 5.2 log reduction (average of 2 runs) in thenumber of S. aureus CFUs and a 5.5 log reduction (average of 2 runs) inthe number of P. aeruginosa CFUs.

Although specific embodiments have been illustrated and described hereinfor purposes of description of the preferred embodiments, it will beappreciated by those of ordinary skill in the art that a wide variety ofalternate or equivalent implementations calculated to achieve the samepurposes may be substituted for the specific embodiments shown anddescribed without departing from the scope of the present invention.This application is intended to cover any adaptations or variations ofthe preferred embodiments discussed herein. Therefore, it is manifestlyintended that this invention be limited only by the claims and theequivalents thereof.

1. A method for treating chronic otitis media and other bacterial earconditions, which method comprises: a) applying a solvating systemcomprising greater than 0.2 wt. % surfactant to a treatment sitecomprising a bacterial biofilm attached or adhered to at least a portionof the middle or inner ear, b) detaching, removing or otherwisedisrupting at least a part of the biofilm, and c) applying to thetreatment site a protective layer of a polymeric film-forming medicalsealant.
 2. A method according to claim 1 wherein the treatment site isin the middle ear.
 3. A method according to claim 1 wherein thetreatment site is in the inner ear.
 4. A method according to claim 1comprising applying the solvating system by spraying, lavage, misting,mopping, wicking or dripping and further comprising removing thesolvating system from the treatment site by flushing, rinsing, drainingor absorption.
 5. A method according to claim 1 comprising applying thesealant by spraying, lavage, misting, mopping, wicking or dripping.
 6. Amethod according to claim 1 comprising applying the solvating system andsealant directly in the middle or inner ear.
 7. A method according toclaim 6 comprising applying the sealant as a film or conformal coating.8. A method according to claim 7 comprising applying the sealant withoutfilling the middle or inner ear.
 9. A method according to claim 1wherein the surfactant comprises an anionic surfactant, nonionicsurfactant, cationic surfactant, zwitterionic surfactant or mixturethereof.
 10. A method according to claim 1 wherein the surfactantcomprises an alkyl sulfate, alkyl sulfonate or aryl sulfonate.
 11. Amethod according to claim 1 wherein the surfactant is about 0.3% toabout 30% of the solvating system.
 12. A method according to claim 1wherein the surfactant is about 0.5% to about 25% of the solvatingsystem.
 13. A method according to claim 1 wherein the solvating systemfurther comprises a metal ion sequestering agent.
 14. A method accordingto claim 13 wherein the metal ion sequestering agent comprises asequestering agent for sodium, calcium or iron.
 15. A method accordingto claim 13 wherein the metal ion sequestering agent comprises citricacid.
 16. A method according to claim 13 wherein the metal ionsequestering agent is present at a concentration of about 0.01 to about0.5 M.
 17. A method according to claim 1 wherein the solvating systemfurther comprises water and has a pH of about 5 to about 8.5.
 18. Amethod according to claim 17 wherein the solvating system furthercomprises a buffer.
 19. A method according to claim 1 wherein thesolvating system further comprises an antimicrobial agent.
 20. A methodaccording to claim 1 wherein the sealant is viscoelastic.
 21. A methodaccording to claim 1 wherein the sealant hardens after application. 22.A method according to claim 1 wherein the sealant comprises apolysaccharide.
 23. A method according to claim 22 wherein the sealantcomprises cellulose, chitin, chitosan, dextran, glycogen,glycosaminoglycan, gum, pectin, starch, or a derivative thereof.
 24. Amethod according to claim 1 wherein the sealant comprises hyaluronan.25. A method according to claim 1 wherein the sealant comprisescarboxymethyl cellulose.
 26. A method according to claim 1 wherein thesealant comprises a lipid or polypeptide.
 27. A method according toclaim 1 wherein the solvating system or sealant further comprises anantimicrobial agent.
 28. A method according to claim 27 wherein theantimicrobial agent comprises gallium acetoacetonate, gallium bromide,gallium chloride, gallium fluoride, gallium iodide, gallium maltolate,gallium nitrate, gallium nitride, gallium percolate, gallium phosphite,gallium sulfate or mixture thereof.
 29. A method according to claim 1further comprising applying an antimicrobial agent after application ofthe solvating system and before application of the sealant.
 30. A methodaccording to claim 1 wherein the same steps performed in vitro willcause greater than a 1-log order reduction in a population of one ormore of Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcuspneumonia, Haemophilus influenzae or Moraxella catarrhalis bacteria. 31.A method according to claim 1 wherein the same steps performed in vitrowill cause greater than a 2-log order reduction in a population of oneor more of Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcuspneumonia, Haemophilus influenzae or Moraxella catarrhalis bacteria. 32.A method according to claim 1 wherein the same steps performed in vitrowill cause greater than a 3-log order reduction in a population of oneor more of Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcuspneumonia, Haemophilus influenzae or Moraxella catarrhalis bacteria. 33.A method according to claim 1 wherein the sealant further comprises ananti-fungal agent, antihistamine, steroidal or non-steroidalanti-inflammatory agent, anti-parasitic agent, antiviral agent,chemotherapeutic/antineoplastic agent, decongestant or mucolytic.